Concentric lines and circuits therefor



CONCENTRIC LINES AND CIRCUITS THEREFOR Filed Jan. 21, 1957 REM/7107 INVENTOR PAUL 0.2mm

ATTORNEY Patented Nov. 26, 1940 i UNITED S ATES PATENT oFHcE 2,222,644 I I GONCENTRIC LINES AND'CIRCUITS p Q THEREFOR I 1 Paul D. 'zbtt'u, West Caldwell, N. -.I., as'signortq I Radio poration of America, a corporation of Delaware I Application January 21, 1937, Serial No. 121,498

3 Claims. (01. 178-44) This invention relates to ultra short wave radio and wherein the input terminals correspond to circuits, particularly of the concentric line type, the leads which connect with tank circuit I3, and the associated circuits therefor. The priand the output terminals correspond to the leads mary object of the present invention is to prowhich connect with amplifier I. Itwill be ob- 5 vide novel constructions of concentric line tuned servable, of course, that the input and output circuits and novel uses therefor in associated terminals might be reversed wherever desirable.

circuits, The coil inductance of Fig. 10. corresponds to the In the accompanying drawing, Fig. 1 illusuniformly distributed inductanceof conductors trates a concentric line tuned circuit used as I and 2, while the capacity of Fig. la corresponds an auto-transformer; Fig. 1a shows the equivato the concentrated capactiance between plates 10 lent circuit diagram for the concentric line of 4 and 5 of Fig. 1 plus the distributed capacity Fig, 1. along the lengths of conductors I, 2. Although Referring to Fig. 1 in more detail, there is terminal I2 is shown as fixed and connected in shown a concentric line tuned circuit comprising Fig. l to the plate 4, one may connect lead I2 an inner conductor I and a concentric outer to a point on conductor I intermediate the ends 15 conductor 2 conductively coupled together at one thereof so as to obtain the desired impedance end 3 and capacitively coupled together at their match between the tuned circuit and the amother end by means of a capacity plate 4 conplifier I, While at the same time maintaining ductively connected to the inner conductor I and the desired selective characteristics of the tuned spaced from end plate 5'fastened to the end of circuit. 7 20 the outer conductor 2, this concentric line being An advantage of the tuned concentric circuit used as an impedance transforming device for of Fig. 1 is that the length-of conductor I can radio frequencies between a suitable oscillation be changed by the knob II to obtain a desired generation circuit 6 and a radio frequency amend capacity between plates 4 and 5 without plifier I. Since the oscillation generator 6 and substantially disturbing the ratio of voltages be- 25 the arnpifier I are well known per se in the art, tween input and output terminals. This is bethey will not be described in detail. cause the total travel of inner conductor I is a The inner conductor I of the concentric line small percentage of its total length. consists of a threaded shaft which engages and What is claimed is: is movable Within a surrounding threaded pipe or 1. An auto-transformer comprising a resonant 30 sleeve 8 to which the input potentials from t e concentric line having an inner and an outer oscillator 6 are applied through a set screw conductor conductively coupled together at one 9 which is threaded into a ring Ill surrounding end and capacitively coupled together at the the pipe 8. The shaft of the inner conductor I other end, said inner conductor being rigid is adjustable in length by means of a suitable throughout its length and including a threaded 35 knob I I which is capable of varying the capac y conducting shaft and surrounding said shaft for between the plates 4 and 5- olltpllt e y is the portion thereofv near said one end a stataken from the tuned circuit by means of a lead tionary conducting sleeve whose interior is I2 which is conductively connected to the plate threaded to cooperate with the threads on said 4 0f the inner C0ndl10t0r l at its pp end a shaft, a knob located externally of said resonant 0 which connects therewith through a tab line and associated with said shaft for moving aperture in the e plate Outer Cond 2 the same with respect to said sleeve, whereby the is Provided With a Suitable Slit Which extends effective length of said inner conductor may be over t e major portion f its length for insllvaried, means surrounding said sleeve and adlatingly a o ating the set screw 9 and for justable in position over the length of said sleeve 45 enabling the Set Screw 9 d ring to be moved for enabling a circuit connection to be made to over the length of the pipe 8 for selection of a i inner conducton suitable potential point on the pipe. In hi 2. An auto-transformer comprising a resonant manner, it is possible 150 match e p nce concentric line having an inner and an outer, of the energ c t l3 0 the impedance conductor conductively coupled together at one 50 of the amplifier I. end and capacitively coupled together at the In eifect, the concentric line I, 2 is an autoother end, said inner conductor being rigid transformer, as will be more readily observable throughout its length and including a threaded upon inspection of Fig. 1a which shows the conducting shaft and surrounding said shaft for equivalent circuit diagram of the concentric line, the portion thereof near said one end a sta- 55 2 tionary conducting sleeve whose interior is threaded to cooperate with the threads on said shaft, a knob located externally of said resonant line and associated with said shaft for moving the same with respect to said sleeve, whereby the effective length of said inner conductor may be varied, a metallic ring surrounding said sleeve, said outer conductor being provided with a slot extending longitudinally thereover for enabling connection to be made to said ring.

3. An auto-transformer comprising a resonant concentric line having an inner and an outer conductor conductively coupled together at one end and capacitively coupled together at the other end, said inner conductor being rigid throughout its length and including a threaded conducting shaft and surrounding said shaft for the portion thereof near said one end a stationary conducting sleeve whose interior is threaded to cooperate with the threads on said shaft, a knob located externally of said resonant line and associated with said shaft for moving the same with respect to said sleeve, whereby the efiective length of said inner conductor may be varied, a metallic ring surrounding said sleeve and in direct contact therewith, said ring being adjustable over the length of said sleeve, said outer conductor being provided with a slot extending longitudinally thereover for enabling connection to be made to said ring at various positions over the length of said sleeve.

PAUL D. ZO'ITU. 

